Firmness, dry-matter and soluble-solids assessment of postharvest kiwifruit by NIR spectroscopy
V. Andrew McGlone and Sumio Kawano
Postharvest Biology and Technology Vol: 13 Issue: 2 Pages: 131-141
1998
บทคัดย่อ
NIR spectroscopy was used to test whether postharvest ripeness and physicochemical properties of kiwifruit (Actinidia deliciosa (A. Chev.) C.F. Liang et A.R. Ferguson cv. `Hayward') could be determined non-destructively. Multivariate models for predicting firmness, dry matter, and soluble solids were developed from NIR interactance measurements using a narrow spectral range from 800 to 1100 nm. Dry matter and soluble solids could both be predicted with very good accuracy. Overall regression statistics in prediction were: R2=0.90, root mean square error of prediction (RMSEP)=0.42% for dry-matter; and R2=0.90, RMSEP=0.39°Brix for soluble solids content. Firmness was not well predicted with overall prediction statistics of R2=0.66 and RMSEP=7.8 N. Within a narrow fruit data set, in terms of orchard origin and size, a better firmness model could be produced (R2=0.76, RMSEP=7.0 N). However this model performed poorly against independent data sets, suggesting the influence of secondary correlations due to fruit characteristics that are not directly related to fruit firmness.